enough, health, later,  pass, slowly, ,  population , fast ,  number,  mean,  much

 
Ten thousand years ago, the world’s  【小题1】 was very small. For several thousand years it grew quite 【小题2】 . But during the last three or four hundred years it has grown very 【小题3】. Two thousan years ago , there were only 250 million people on the earth. One thousand six hundred years  【小题4】 , the  【小题5】 was over 500 million . In 1990, there were over five bilion. A UN report said that the word’s population would   【小题6】 six billion by the end of this century. This is just ten years after it reaches five billion. This 【小题7】  we must grow 【小题8】   food, and have smaller families with fewer, but【小题9】children. If we don’t do these things, the results will be bad. There will not be   【小题10】   space (空间) even to stand on the earth.

Cloze test

There are many problems in the world, but the population problem may be the1 one of the world today. The world's population is growing 2 .Two thousand years ago, there were only 250 million people on the 3 Four hundred years ago, the number was 4 500 million. But at the beginning of the 5 century, the world's population was about 1,700 million. In 1970, this number was 3,600 million. In 1990, the number was five billion. A UN 6 said that the world's population had 7 six billion by the end of the 21th century. This is just ten 8 after it 9 five billion. People say that by the year 2010, 10 may be seven billion.